Prom 1969 to 1971, king salmon population estimates obtained by carcass survey techniques on the Feather River were compared with estimates made by mark and recovery and electronic fish-counter methods. In a low-flow river area, the carcass survey estimates were from six to nine percent lower than the electronic fish count estimates. Also, in the low-flow reach of the river, the carcass survey was from three to 15 percent higher than the mark and recovery estimates. In high-flow river areas, the carcass recovery estimates were from one to six percent lower than mark and recovery values. Under field conditions in the Feather River, the carcass survey method produces valid salmon population estimates.
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